Forum OpenACS Q&A: Response to Open ACS kernel + ACS modules
Don and Ben's points are not that ACS Java is bad, just that aDPL was written in such a way that could endanger the freedom of OpenACS. There are any number of reasons they did this and I don't think they did it to undermine OpenACS.
aD is not in the clear yet. It's not assured aD will exist in a year. In case they go under or are absorbed by another company there's no telling what might happen to that code. And by extension, there's no telling what will happen to any code that's been derived from ACS4.6 or beyond. That's why it's important that OpenACS developers maintain a clear separation from the current aD code.
As the representative of a company that is committed to OpenACS and is a partner of aD, we're in a little weird position. We would love to take advantage of ACS Java, but are also actively developing on the OpenACS platform. So it seems aD effectively made us choose to go one way or the other, not enjoy the best of both worlds, with the aDPL simply because we are not interested in endangering the freedom OpenACS enjoys under the GPL.
I really hope that this stuff will be cleared up soon, or it's going to put a lot of people in very difficult positions. I don't necessarily have a problem with their license switch, but I have to admit I'm once again disappointed with the way they dealt with their community.